Publisher Health

An air filter made out of corn protein instead of petroleum products can concurrently capture small particulates as well as toxic chemicals like formaldehyde that current air filters can’t.
The research could lead to better air purifiers, particularly in regions of the world that suffer from very poor air quality. Washington State University engineers report on the design and tests of materials for this bio-based filter in the journal Separation and Purification Technology.
“Particulate matter is not that challenging to filter but to simultaneously capture various kinds of chemical gas molecules, that’s more significant,” said Katie Zhong, professor in WSU’s School of Mechanical and Materials Engineering and a corresponding author on the paper. “These protein-based air filtering materials should be very promising to capture multiple species of air pollutants.”
Poor air quality is a factor in diseases such as asthma, heart disease and lung cancer. Commercial air purifiers remove tiny particles in soot, smoke or car exhaust, which could be inhaled directly into the lungs, but air pollution also often contains other hazardous gaseous molecules, such as carbon monoxide, formaldehyde and other volatile organic compounds.
With micron-sized pores, typical high efficiency particulate air filters, also known as HEPA filters, can capture the small particles but aren’t able to capture gaseous molecules. They are most often made of petroleum products and glass, which leads to secondary pollution when old filters are thrown away, Zhong said.
The WSU researchers developed a more environmentally friendly air filter made from corn protein fibers that was able to simultaneously capture 99.5% of small particulate matter, similar to commercial HEPA filters, and 87% of formaldehyde, which is higher than specially designed air filters for those types of toxics.
The researchers chose corn to study because of its abundance as an agricultural product in the U.S. The corn protein is also hydrophobic, which means that the protein repels water and could work well in a moist environment such as in a mask.
The amino acids in the corn protein are known as functional groups. When exposed at the protein’s surface, these functional groups act like multiple hands, grabbing the toxic chemical molecules. The researchers demonstrated this by exposing a functional group at the protein surface, where it grabbed formaldehyde. They theorize that further rearrangement of the proteins could develop a tentacle-like set of functional groups that could grab a variety of chemicals from the air.
“From the mechanism, it’s very reasonable to expect that this protein-based air filter could capture more species of toxic chemical molecules,” Zhong said.
The three-dimensional structure that they developed also offers more promise for a simple manufacturing method than thin films of proteins that the research team developed previously. They used a small amount of a chemical, polyvinyl alcohol, to glue the nanofibers together into a lightweight foam-like material.
“This work provides a new route to fabricating environmentally friendly and multi-functional air filters made from abundant natural biomass,” Zhong said. “I believe this technology is very important for people’s health and our environment, and it should be commercialized.”
The researchers would like to do more testing, including using a variety of functional group structures and other toxic chemical molecules. In addition to Zhong, the work was conducted by graduate student Shengnan Lin, Ming Luo, Flaherty assistant professor in the WSU School of Mechanical and Materials Engineering, and post-doctoral fellow Xuewei Fu. The work was funded by a U.S. Department of Agriculture Sun Grant.

Snakes bite 5.4 million people each year — and roughly half are injected with venom, according to the WHO. Between 81,000 and 138,000 people die, while around three times as many suffer amputations and other permanent disabilities. Due to their size, children often suffer the most severe effects.
For 128 years, our primary treatment against snakebite has been using mixtures of polyclonal antibodies derived from immunized animal blood. Although they are proven effective, these medicines may cause adverse reactions that can sometimes be severe. So, the search for novel ways to treat severe snakebite envenoming is ongoing.
Recently, an international team of scientists led by DTU reached remarkable results and developed a new modernized prototype treatment that proves effective against the venom of African and Asian elapid snakes, such as some cobra, mamba, and krait species — many of which are among the world’s deadliest.
“We have previously developed antibodies against the venom toxins from single snake species; however, our new results demonstrate that our technology has great potential in neutralizing toxins from multiple species, even from different continents. This broadened cross-neutralization capacity is very promising. It could provide the basis for more effective treatments for snakebite victims in the future,” says Andreas Hougaard Laustsen-Kiel, a professor at DTU Bioengineering.
He conducted the research with colleagues at DTU, ETH Zurich, Universidad de Costa Rica, and industrial partners Sophion Bioscience and IONTAS. Their work is published in Nature Communications.
New antibody works against several neurotoxins
In essence, their approach is to develop antibodies of fully human origin, which offer fewer adverse reactions, competitive costs, and, when fine-tuned, superior efficacy. They use phage display technology, a popular in vitro methodology within drug discovery, to select antibodies that bind well to the toxins in the venom, enabling broad neutralization.

“There has been a revolution in recombinant antibody technology over the last three decades. I am delighted to be involved in these efforts to direct phage display technology to the blight of snakebite envenomation,” says John McCafferty, the inventor of antibody phage display. He founded IONTAS and has recently established a new anti-venom group at the University of Cambridge.
Deliberately selecting hundreds of antibody candidates and testing the most promising against toxins in different snake venoms, the researchers found that one in particular (2554_01_D11) was especially potent and broadly neutralizing. It bound to various neurotoxins present in the venoms of the monocled cobra, the forest cobra, the spectacled cobra, the king cobra, the black mamba, and the many-banded krait.
Subsequent in vivo studies showed that the antibody prevented or delayed death from venom. For the monocled cobra specifically, the antibody completely prevented lethality in envenomed mice.
“In light of the positive results regarding the neutralization of venom from the monocled cobra, we mimicked a true rescue situation, injecting mice with cobra venom and then administering the antibody. And sure enough, we were able to prevent death when the antibody was injected rapidly after envenoming,” says José María Gutiérrez, emeritus professor of Instituto Clodomiro Picado, University of Costa Rica.
While the antibody could not prevent death from black mamba venom, survival was prolonged by several hours, suggesting that the antibody provided a partial neutralization of the venom.
“These are remarkable results,” says Andreas Hougaard Laustsen-Kiel:
“The antibody we used worked against different neurotoxins derived from different snake species from different parts of the world. These toxins are far from identical but share some crucial similarities in their structure. And apparently, these are just enough for our antibody to display extensive cross-reactivity. We have yet to establish the boundaries of what this antibody can neutralize. Still, we would like to see if it shows the same promise concerning neurotoxins from, for example, the blue krait, the banded krait, and the Egyptian cobra.”
The researchers expect antibodies, such as 2554_01_D11, will be helpful when designing future envenoming therapies. At the same time, however, they stress that their pipeline for discovery could be useful in developing other broadly neutralizing antibodies against toxins from other animals, bacteria, viruses, and parasites or even in developing cancer therapies.

Using ensemble learning techniques and longitudinal data from a large naturalistic driving study, researchers at Columbia University’s Mailman School of Public Health, Fu Foundation School of Engineering and Applied Science, and Vagelos College of Physicians and Surgeons have developed a novel, interpretable and highly accurate algorithm for predicting mild cognitive impairment and dementia in older drivers. Digital markers refer to variables generated from data captured through recording devices in the real-world setting. These data could be processed to measure driving behavior, performance and tempo-spatial pattern in exceptional detail. The study is published in the journal Artificial Intelligence in Medicine.
The researchers used an interaction-based classification method for selecting predictive variables in the dataset. This learning model has achieved an accuracy of 96 percent in predicting mild cognitive impairment and dementia, outperforming traditional machine learning models such as logistic regression and random forests — a statistical technique widely used in AI for classifying disease status. “Our new ensemble learning model based on digital markers and basic demographic characteristics could predict mild cognitive impairment and dementia in older drivers with excellent accuracy,” said Sharon Di, associate professor of civil engineering and engineering mechanics at Columbia Engineering and the study’s lead author.
The investigators constructed 200 variable modules using the naturalistic driving data on the driver, the vehicle and the environment captured by in-vehicle recording devices for 2977 drivers participating in the Longitudinal Research on Aging Drivers (LongROAD) project, a prospective cohort study conducted in five sites across the contiguous United States and sponsored by the AAA Foundation for Traffic Safety. At the time of enrollment, the participants were active drivers aged 65-79 years who were cognitively intact. Data used in this study came from the first three years of follow-up, spanning from August 2015 through March 2019. During the follow-up, 36 participants were diagnosed with mild cognitive impairment, 8 with Alzheimer’s disease, and 17 with other or unspecified dementia.
The researchers performed a series of computer modeling experiments and found that the new ensemble learning model is 6-10 percent more accurate than random forests and logistic regression models in predicting mild cognitive impairment and dementia. The two most influential driving variables are the right to left turn ratio and the number of hard braking events (defined as maneuvers with deceleration rates ≥ 0.4 g). “With advancing age, drivers make relatively fewer left turns and more right turns because left turns are riskier,” noted Di.
“About 85 percent of older adults in the United States are licensed drivers. As the most preferred mode of personal transportation, driving plays an important role in maintaining independence, self-control, social connection, and quality of life. Safely operating a car requires essential cognitive and physical functions. Our study indicates that digital markers embedded in routinely collected driving data can be used through innovative machine learning techniques as valid and reliable artificial intelligence for predicting mild cognitive impairment and dementia,” said Guohua Li, MD, DrPH, professor of epidemiology and anesthesiology at Columbia Mailman School of Public Health and Vagelos College of Physicians and Surgeons, and senior author. “Early detection of mild cognitive impairment and dementia could lead to timely evaluation, diagnosis, and interventions, which are especially salient in the absence of effective therapeutics.”
Co-authors are Carolyn DiGuiseppi, Colorado School of Public Health; David W. Eby, University of Michigan Transportation Research Institute; Linda Hill, University of California San Diego School of Public Health; Thelma J. Mielenz, Columbia Mailman School of Public Health; David Strogatz, Bassett Research Institute; and Minjae Kim, Columbia Vagelos College of Physicians and Surgeons.
The study was supported in part by the AAA Foundation for Traffic Safety.

Teens and young adults who reduced their social media use by 50% for just a few weeks saw significant improvement in how they felt about both their weight and their overall appearance compared with peers who maintained consistent levels of social media use, according to research published by the American Psychological Association.
“Adolescence is a vulnerable period for the development of body image issues, eating disorders and mental illness,” said lead author Gary Goldfield, PhD, of Children’s Hospital of Eastern Ontario Research Institute. “Youth are spending, on average, between six to eight hours per day on screens, much of it on social media. Social media can expose users to hundreds or even thousands of images and photos every day, including those of celebrities and fashion or fitness models, which we know leads to an internalization of beauty ideals that are unattainable for almost everyone, resulting in greater dissatisfaction with body weight and shape.”
However, much of the psychological research on social media, body image and mental health is correlational, according to Goldfield, so it is uncertain whether people with body image and mental health issues spend more time on social media or if social media use leads to greater body image and mental health issues.
To better understand the causal effects of reducing social media use on body image, Goldfield and his colleagues previously conducted a pilot study with 38 undergraduate students with elevated levels of anxiety and/or depression. Some of the participants were asked to limit their social media use to no more than 60 minutes per day, while others were allowed unrestricted access. Compared with participants who had unlimited access, participants who restricted their use showed improvements in how they regarded their overall appearance (but not their weight) after three weeks. Due to the small sample size, though, the researchers were unable to conduct a meaningful analysis of the effect of gender.
The current experiment, involving 220 undergraduate students aged 17-25 (76% female, 23% male, 1% other) and published in the journal Psychology of Popular Media, sought to expand the pilot study and address the gender limitation. In order to qualify, participants had to be regular social media users (at least two hours per day on their smartphones) and exhibit symptoms of depression or anxiety.
For the first week of the experiment, all participants were instructed to use their social media as they normally would. Social media use was measured using a screen-time tracking program to which participants provided a daily screenshot. After the first week, half the participants were instructed to reduce their social media use to no more than 60 minutes per day. At the start of the experiment, participants also responded to a series of statements about their overall appearance (e.g., “I’m pretty happy about the way I look,”) and weight (e.g., “I am satisfied with my weight,”) on a 5-point scale, with 1 indicating “never” and 5 “always.” Participants completed a similar questionnaire at the end of the experiment.
For the next three weeks, participants who were instructed to restrict their social media use reduced it by approximately 50% to an average of 78 minutes per day versus the control group, which averaged 188 minutes of social media use per day.
Participants who reduced their social media use had a significant improvement in how they regarded both their overall appearance and body weight after the three-week intervention, compared with the control group, who saw no significant change. Gender did not appear to make any difference in the effects.
“Our brief, four-week intervention using screen-time trackers showed that reducing social media use yielded significant improvements in appearance and weight esteem in distressed youth with heavy social media use,” said Goldfield. “Reducing social media use is a feasible method of producing a short-term positive effect on body image among a vulnerable population of users and should be evaluated as a potential component in the treatment of body-image-related disturbances.”
While the current study was conducted as a proof of concept, Goldfield and his colleagues are in the process of conducting a larger study to see if reduction in social media use can be maintained for longer periods and whether that reduction can lead to even greater psychological benefits.

A new study in Biological Psychiatry, published by Elsevier, explores the interplay between the serotonin system and estradiol in the brain, showing that the central nervous system in patients with premenstrual dysphoric disorder (PMDD) seems to increase serotonin transporter density from the periovulatory phase (when estradiol levels are high) to premenstrual cycle phase (when both estradiol and progesterone are decreasing). The findings have the potential to advance the clinical treatment of PMDD.
Premenstrual syndrome (PMS), which can include physical symptoms as well as depression and anxiety, affects about half of menstruating individuals a few days before the onset of menstruation. About 3 to 8% of people who menstruate experience PMDD, a far less recognized diagnosis. PMDD is also associated with mood swings, depression, and anxiety, but its symptoms are more severe and can last for up to two weeks at a time. The lifetime toll of PMDD is comparable to that for people with major depressive disorder.
Previous studies that compared fluctuations in ovarian hormones between women with PMDD and healthy women interestingly found no substantial differences, suggesting that dysregulated hormones in the periphery are not the underlying cause of the disorder. An alternative idea is that the brain’s response to normal endogenous hormonal changes differs in patients with PMDD, although how that happens remains unclear. Treatment of PMDD with selective serotonin reuptake inhibitors, or SSRIs, results in remarkably rapid alleviation of symptoms — on the order of hours or days, rather than weeks as in treatment for depression.
In the current study, led by Julia Sacher, MD, PhD, from the Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, examined 30 patients with PMDD and 29 unaffected control women over the course of two menstrual cycles. The researchers used positron emission tomography (PET) imaging to visualize availability of the serotonin transporter protein in the brain throughout the cycle, reflecting short-term changes in its expression.
“We found a significant increase of serotonin transporter from periovulatory to premenstrual phase in patients with PMDD — an 18% change in the midbrain, a brain region with the richest serotonin transporter expression. This increase was associated with the severity of depressed mood premenstrually,” said Dr. Sacher.
Unexpectedly, Dr. Sacher and colleagues also found a decrease in midbrain serotonin transporter density in healthy women, which could point to a protective mechanism of the healthy female brain in the midst of a changing hormonal environment.
“Typically, it is assumed that serotonin transporter density is an individual trait, with only an approximately 10% change over a decade as the human brain ages, rather than a state that changes within shorter periods of time. However, studies in patients with seasonal affective disorder (SAD) show seasonal changes of serotonin transporter,” Dr. Sacher explained. “Although the reports of serotonin transporter availability in depression have been mixed, this may be due to the heterogeneity of that disease. In more homogenous types of affective disorders, such PMDD or SAD, relatively rapid dynamics of serotonin transporter availability seem to play an important role.”
John Krystal, MD, editor of Biological Psychiatry, said of the work, “This technically demanding study identifies a new potential mechanism contributing to negative premenstrual mood states in some women. It also supports the use of SSRIs to treat premenstrual dysphoric mood.”
The findings provide evidence that individuals with PMDD experience short-term changes in serotonin transporter density throughout the menstrual cycle, which suggests that patients might benefit from taking SSRIs at specific times during the cycle to best target these changes.

As air pollution in Stockholm has decreased, so has the lung capacity of children and adolescents has improved, a new study published in the European Respiratory Journal reports. The researchers from Karolinska Institutet consider the results important, since the lung health of the young greatly affects the risk of their developing chronic lung diseases later in life.
“Fortunately, we’ve seen a decrease in air pollutants and therefore an increase in air quality in Stockholm over the past 20 years,” says the study’s last author Erik Melén, paediatrician and professor at the Department of Clinical Research and Education, Karolinska Institutet. “We therefore also wanted to examine if the lungs of children also improved during this period.”
The adverse impact of airborne pollutants on children’s lung health are well-documented. According to the researchers, however, how changes in air quality can affect lung development in children and adolescents is less studied.
The study used a cohort from the BAMSE project, in which researchers have been following some 4,000 individuals born between 1994 and 1996. The children were given a questionnaire to answer and spirometric examinations to test their lung function at the ages of 8, 16 and 24.
The researchers estimated, above all, concentrations of airborne pollutants, mostly from traffic, at sites where the participants lived from birth until early adulthood.
In general, air pollution was around 40 per cent lower in Stockholm between 2016 and 2019 than it was between 2002 and 2004. At some locations, such as Hornsgatan on Södermalm, it had decreased by 60 per cent; at others, there was no significant difference in air quality.

“When we compare the individuals living in the areas in which air quality has improved and those in which it hasn’t, we find that lung function improved by a few per cent in the participants in the young adult age bracket,” says the study’s first author Zhebin Yu, postdoc researcher at the Institute of Environmental Medicine, Karolinska Institutet. “But above all we could see a 20 per cent lower risk of having significantly impaired lung function.”
The researchers conclude that lower exposure to airborne pollutants, even at relatively low levels, is associated with improvements in the development of lung function from childhood to early adulthood.
The results are important, says Professor Melén, since optimal lung development during childhood is a powerful determinant of good health in adulthood.
“It is ultimately of great importance since the lung function that children and adolescents develop as they grow up persists into adulthood,” he explains. “If you have reduced lung function as an adult, you run a greater risk of chronic lung diseases like COPD, cardiovascular disease and premature death. So by improving air quality, we reduce the likelihood of children developing chronic diseases later in life.”
Previous studies from the BAMSE project have shown that lung function growth can both improve and deteriorate over time, and these new results show that air pollution can play an important part in this.
“Airborne pollutants that are by nature persistent are a great worry and our study clearly indicates that efforts to improve air quality have paid off, with quantifiable improvements in child and adolescent health,” says Professor Melén.
The next step is to examine potential advantages of cleaner air for lung diseases like asthma, bronchitis and prodromal COPD and for cardiometabolic diseases such as cardiovascular disease and type 2 diabetes.
The study was conducted in collaboration with SLB-analys, Stockholm South (Söder) General Hospital and Region Stockholm’s Centre for Occupational and Environmental Medicine, and was financed by the European Research Council, the Swedish Research Council, the Swedish Heart-Lung Foundation and the Swedish Research Council for Health, Working Life and Welfare.

Scientists at Open Targets, EMBL’s European Bioinformatics Institute (EMBL-EBI), and GSK are revealing the shared basis of diseases using a map of interacting human proteins. By helping to understand how biological processes affect human traits and diseases, this work will prioritise new targets for drug discovery and identify drug repurposing opportunities.
Proteins are molecules that do most of the work in our cells and are made following blueprints encoded in genes. They are essential for the structure, function, and regulation of the body’s tissues, and are often the target of drugs or therapies.
Genome Wide Association Studies (GWAS) help us establish the genetic basis of disease by linking specific genes to diseases. To determine how those genes contribute to disease, we need to understand the function of the proteins they encode and link specific biological processes to diseases.
In this new study, published in the journal Nature Genetics, researchers created a network of interacting proteins — or an interactome — combining evidence from different sources, including EMBL-EBI’s IntAct database, Reactome, and Signor. Using this interactome, they identified groups of proteins interacting with genes that have been linked through GWAS to over 1,000 human traits from 21 therapeutic areas.
Guilt-by-association
Proteins that interact with each other will likely be involved in the same biological processes. Therefore, if a protein is known to be involved in a disease, knowing which partners it interacts with provides information about the function it has in a cell. Through ‘guilt-by-association’, the interacting proteins can also sometimes be excellent therapeutic targets.

The researchers found 73 clusters of proteins that were linked to more than one trait or disease, a phenomenon known as pleiotropy. Understanding these pleiotropic relationships is invaluable to drug discovery because they indicate opportunities where a therapy for one disease might be effective in another. They can also suggest drug targets to avoid, when targeting them may cause unwanted side effects.
“The interactome identified some known associations, such as cardiovascular diseases and lipoprotein or cholesterol measurements,” said Inigo Barrio Hernandez, postdoctoral fellow at Open Targets and EMBL-EBI. “But we also found some unexpected associations. For example, the interactome highlighted three protein clusters shared by ten respiratory and skin immune-related diseases. This is hugely exciting because we now have some biological support to repurpose existing drugs that are proven to be safe to treat related diseases.”
Finding the cause of diseases
The network expansion is also a useful tool to assess the relative importance of genes at genomic loci identified through GWAS. GWAS compare points of common variation in the human genome between individuals with a specific trait or disease and control individuals. To identify the likely causative genes and proteins linked to the trait in question, prediction methods such as Open Targets’s Locus-to-Gene machine learning score have been developed. This method uses factors such as the distance from the point of common variation to the gene and the structure of the DNA in that location to prioritise the most relevant genes.
In the present study, the researchers showed that the interactome could be used to find the proteins most likely to be involved in causing disease, using Inflammatory Bowel Disease (IBD) as an example. IBD is a complex disease with a genetic basis, but for which the disease biology is not well understood. In collaboration with Open Targets researchers who specialise in IBD, Barrio Hernandez demonstrated that the interactome could be used to prioritise a list of proteins most likely involved in the disease, based on their proximity to other IBD-linked proteins in the interactome.
“This work bridges many fields of biology, including statistical genetics, cell biology, and bioinformatics,” said Pedro Beltrao, Associate Professor at ETH Zurich and former Group Leader at EMBL-EBI. “It brought together groups from across Open Targets and EMBL-EBI, and highlights the value of collaborations across disciplines.”
“This is an exciting showcase of one of our Open Targets collaborative informatics projects that has generated an array of new insights for novel target discovery as well as drug repurposing, and informs our understanding of the connection between rare and common diseases through shared biological processes,” said Ellen McDonagh, Director of Informatics Science at Open Targets. “This is now being developed further to provide tissue and cell-type specific networks to help further prioritise targets for disease treatment.”

Scientists have successfully recorded brain activity from freely moving octopuses, a feat made possible by implanting electrodes and a data logger directly into the creatures.
The study, published online in Current Biology on February 23, is a critical step forward in figuring out how octopus’ brains control their behavior, and could provide clues to the common principles needed for intelligence and cognition to occur.
“If we want to understand how the brain works, octopuses are the perfect animal to study as a comparison to mammals. They have a large brain, an amazingly unique body, and advanced cognitive abilities that have developed completely differently from those of vertebrates,” said Dr. Tamar Gutnick, first author and former postdoctoral researcher in the Physics and Biology Unit at the Okinawa Institute of Science and Technology (OIST).
But measuring the brainwaves of octopuses has proven a real technical challenge. Unlike vertebrates, octopuses are soft bodied, so they have no skull to anchor the recording equipment onto, to prevent it being removed.
“Octopuses have eight powerful and ultra-flexible arms, which can reach absolutely anywhere on their body,” said Dr. Gutnick. “If we tried to attach wires to them, they would immediately rip if off, so we needed a way of getting the equipment completely out of their reach, by placing it under their skin.”
The researchers settled on small and lightweight data loggers as the solution, which were originally designed to track the brain activity of birds during flight. The team adapted the devices to make them waterproof, but still small enough to easily fit inside the octopuses. The batteries, which needed to work in a low-air environment, allowed up to 12 hours of continuous recording.

The researchers chose Octopus cyanea, more commonly known as the day octopus, as their model animal, due to its larger size. They anesthetized three octopuses and implanted a logger into a cavity in the muscle wall of the mantle. The scientists then implanted the electrodes into an area of the octopus’ brain called the vertical lobe and median superior frontal lobe, which is the most accessible area. This brain region is also believed to be important for visual learning and memory, which are brain processes that Dr. Gutnick is particularly interested in understanding.
Once the surgery was complete, the octopuses were returned to their home tank and monitored by video. After five minutes, the octopuses had recovered and spent the following 12 hours sleeping, eating and moving around their tank, as their brain activity was recorded. The logger and electrodes were then removed from the octopuses, and the data was synchronized to the video.
The researchers identified several distinct patterns of brain activity, some of which were similar in size and shape to those seen in mammals, whilst others were very long lasting, slow oscillations that have not been described before.
The researchers were not yet able to link these brain activity patterns to specific behaviors from the videos. However, this is not completely surprising, Dr. Gutnick explained, as they didn’t require the animals to do specific learning tasks.
“This is an area that’s associated with learning and memory, so in order to explore this circuit, we really need to do repetitive, memory tasks with the octopuses. That’s something we’re hoping to do very soon!”
The researchers also believe that this method of recording brain activity from freely moving octopuses can be used in other octopus species and could help solve questions in many other areas of octopus cognition, including how they learn, socialize and control the movement of their body and arms.
“This is a really pivotal study, but it’s just the first step,” said Prof. Michael Kuba, who led the project at the OIST Physics and Biology Unit and now continues at the University of Naples Federico II. “Octopus are so clever, but right now, we know so little about how their brains work. This technique means we now have the ability to peer into their brain while they are doing specific tasks. That’s really exciting and powerful.”
The study involved an international collaboration between researchers in Japan, Italy, Germany, Ukraine, and Switzerland.

Fasting may be detrimental to fighting off infection, and could lead to an increased risk of heart disease, according to a new study by the Icahn School of Medicine at Mount Sinai. The research, which focused on mouse models, is among the first to show that skipping meals triggers a response in the brain that negatively affects immune cells. The results that focus on breakfast were published in the February 23 issue of Immunity, and could lead to a better understanding of how chronic fasting may affect the body long term.
“There is a growing awareness that fasting is healthy, and there is indeed abundant evidence for the benefits of fasting. Our study provides a word of caution as it suggests that there may also be a cost to fasting that carries a health risk,” says lead author Filip Swirski, PhD, Director of the Cardiovascular Research Institute at Icahn Mount Sinai. “This is a mechanistic study delving into some of the fundamental biology relevant to fasting. The study shows that there is a conversation between the nervous and immune systems.”
Researchers aimed to better understand how fasting — from a relatively short fast of only a few hours to a more severe fast of 24 hours — affects the immune system. They analyzed two groups of mice. One group ate breakfast right after waking up (breakfast is their largest meal of the day), and the other group had no breakfast. Researchers collected blood samples in both groups when mice woke up (baseline), then four hours later, and eight hours later.
When examining the blood work, researchers noticed a distinct difference in the fasting group. Specifically, the researchers saw a difference in the number of monocytes, which are white blood cells that are made in the bone marrow and travel through the body, where they play many critical roles, from fighting infections, to heart disease, to cancer.
At baseline, all mice had the same amount of monocytes. But after four hours, monocytes in mice from the fasting group were dramatically affected. Researchers found 90 percent of these cells disappeared from the bloodstream, and the number further declined at eight hours. Meanwhile monocytes in the non-fasting group were unaffected.
In fasting mice, researchers discovered the monocytes traveled back to the bone marrow to hibernate. Concurrently, production of new cells in the bone marrow diminished. The monocytes in the bone marrow — which typically have a short lifespan — significantly changed. They survived longer as a consequence of staying in the bone marrow, and aged differently than the monocytes that stayed in the blood.
The researchers continued to fast mice for up to 24 hours, and then reintroduced food. The cells hiding in the bone marrow surged back into the bloodstream within a few hours. This surge led to heightened level of inflammation. Instead of protecting against infection, these altered monocytes were more inflammatory, making the body less resistant to fighting infection.
This study is among the first to make the connection between the brain and these immune cells during fasting. Researchers found that specific regions in the brain controlled the monocyte response during fasting. This study demonstrated that fasting elicits a stress response in the brain — that’s what makes people “hangry” (feeling hungry and angry) — and this instantly triggers a large-scale migration of these white blood cells from the blood to the bone marrow, and then back to the bloodstream shortly after food is reintroduced.
Dr. Swirski emphasized that while there is also evidence of the metabolic benefits of fasting, this new study is a useful advance in the full understanding of the body’s mechanisms.
“The study shows that, on the one hand, fasting reduces the number of circulating monocytes, which one might think is a good thing, as these cells are important components of inflammation. On the other hand, reintroduction of food creates a surge of monocytes flooding back to the blood, which can be problematic. Fasting, therefore regulates this pool in ways that are not always beneficial to the body’s capacity to respond to a challenge such as an infection,” explains Dr. Swirski. “Because these cells are so important to other diseases like heart disease or cancer, understanding how their function is controlled is critical.”
This study was funded by grants from the National Institutes of Health and the Cure Alzheimer”s Fund,

To eat or to mate — that is the question (and the answer is: moderately hungry mice choose to mate). Researchers publishing in the journal Cell Metabolism on Thursday February 23 show that hungry mice prioritize interacting with members of the opposite sex over eating and drinking when their brains are stimulated with leptin, an appetite-suppressing hormone.
“We can only pursue one behavior at a time, so our brain has to somehow compute what will be the most rewarding behavior, or what is our most urgent need,” says senior author Tatiana Korotkova (@CurioNeuro), a neuroscientist at the University Clinic Cologne in Germany.
To elucidate the hierarchy of innate behaviors like eating, drinking, socializing, and mating, Korotkova’s team observed and stimulated mouse neurons within the lateral hypothalamus, one of the main “feeding centers” of the brain. They focused on neurons that bear receptors for leptin and neurons that produce neurotensin, two hormones with ties to hunger and thirst. To their surprise, they found that these neurons were also involved in guiding social behavior and helping the mice balance their nutritional and social needs.
“We were astonished to find that the lateral hypothalamus links feeding and drinking to social behaviors,” says first author Anne Petzold (@neuroadept, @neuroadept@mastodon.online), also a neuroscientist at the University of Cologne. “Activating leptin receptor neurons makes mice prioritize social interaction despite acute hunger or thirst. This makes sense biologically because mating partners are not something that you have around all the time, and so one must be able to ignore hunger or thirst to be able to engage in mating.”
The researchers used tiny microscopes to visualize the activity of individual brain neurons while the mice explored and engaged in various behaviors in an enclosure. “It was a huge advantage that we could record the activity of neurons in a freely behaving animal,” says Korotkova. “We could really see how neuronal activity changes during particular behaviors, and we could track and change the activity of individual cells with a high time precision.”
To see how the mice’s priorities changed according to their hunger level, the team compared the behavior of mice who had unlimited access to food to “acutely hungry” mice (whose food had been restricted overnight) and “chronically hungry” mice (whose food had been restricted for 5 days). The researchers note that this “chronic hunger” can also occur in the wild, where food is not available all the time.

They found that leptin receptor neurons were inhibited when the mice ate and were activated when they interacted with mice of the opposite sex — potential mates — but not when they interacted with mice of the same sex.
Next, the researchers used light and chemical signals to selectively stimulate neurons, which allowed them to observe whether and how this activation altered the mice’s behavior.
Leptin stimulation had little effect on the behavior of sated mice, who were generally more interested in socializing than eating, but when the researchers activated the leptin receptor neurons of acutely hungry mice, their priorities changed: they were slower to approach food, ate less, and spent more time socializing with potential mates.
However, leptin stimulation was not able to override the stronger hunger of chronically food restricted mice, whose appetites were unreduced and priorities unmoved by leptin activation.
“So, we have this system which can only regulate moderate hunger, but not strong hunger,” says Korotkova. “This circuit might contribute to why diets don’t work: it’s not a problem to reduce your food intake for a short time, but it doesn’t work if you try to do it for longer.”
In contrast, when the researchers activated neurotensin neurons, they observed increased drinking behavior at the expense of socializing, both with potential mates and with mice of the same sex.
“We usually think about neurons having a particular function, but we found that one cell can actually encode multiple different stimuli,” says Korotkova. This makes a lot of sense biologically because behaviors need to be coordinated, and it’s much more efficient to coordinate behaviors with the same cell than by many different cell types somehow communicating with each other.”
“Next, we’d like to understand how the activity of these cells changes during the progression of obesity or the development of eating disorders,” says Korotkova.